Our medical policies are designed for informational purposes only and are not an authorization, or an explanation of benefits, or a contract. Receipt of benefits is subject to satisfaction of all terms and conditions of the coverage. Medical technology is constantly changing, and we reserve the right to review and update our policies periodically.

Description

Focused microwave phase array thermotherapy has been investigated as a type of heat therapy for treating either primary breast cancer in conjunction with lumpectomy in patients with early stage breast cancer or as a cytoreductive technique in conjunction with preoperative chemotherapy in patients with advanced breast cancer. Microwave applicators are placed on either side of the compressed breast that, when activated, illuminate a large volume of breast tissue. A probe is placed within the breast to monitor the interstitial temperature. The technique is based on the preferential microwave heating that occurs in high-water content breast carcinoma compared to the surrounding lower water content healthy breast tissues. If successful, the microwave therapy could function similarly to the role of whole breast irradiation therapy after breast-conserving surgery, i.e., by destroying microscopic residual cancer cells. In patients with locally advanced primary breast cancer, microwave thermotherapy may reduce the size of the tumor sufficiently to allow a less invasive surgical procedure to be performed.

Currently, no microwave thermotherapy device that is indicated for the treatment of breast cancer has received approval for marketing from the U.S. Food and Drug Administration (FDA). The Microfocus™ APA 1000 System (Celsion, Columbia, MD) is a device that is currently undergoing clinical trials through the FDA investigational device exemption process (IDE).

Policy

Focused microwave phase array thermotherapy is considered investigational as a treatment of breast cancer.

The use of microwave thermotherapy as a treatment of breast cancer is limited to those institutions participating in the IDE trials. Therefore, patients seeking this treatment may request out of network referral. Participating institutions include:

A literature search based on the MEDLINE database revealed limited published data regarding microwave thermotherapy. Gardner and colleagues reported on the results of a phase I and II clinical trial including 10 patients that reported that the technique is technically feasible. (1) Vargas and colleagues reported on a dose-finding study in 25 patients, performed as part of an Investigational Device Exemption (IDE) trial. Patients underwent thermotherapy at various doses before undergoing surgical resection of breast cancer to determine whether or not the use of thermotherapy before breast-conserving surgery could potentially reduce the incidence of positive surgical margins, and thus the need for re-excision. (2) The following randomized clinical trials are now ongoing (3):

Study 102-00-202

A total of 222 female patients with early-stage primary breast cancer will be randomized (ratio 1:1) either to thermotherapy (at one of two different doses) plus surgery or surgery alone. The primary endpoints include reduction of tumor cells at surgical margins and reduction of second incision rates due to unclean surgical margins.

Study 102-00-201

A total of 228 female patients with locally advanced primary breast cancer will be randomized (ratio 1:1) either to chemotherapy plus thermotherapy or chemotherapy alone. The primary endpoints include downsizing from mastectomy to partial mastectomy, and determining the percentage of patients with > =85% pathological cell death.

2006 Update

A search of the literature was performed for the period of 2005. No additional studies were identified that would prompt a reconsideration of the policy statement, which remains unchanged.

2007-2008 Update
A search of the literature was conducted using MEDLINE in December 2007. No publications of results of additional clinical studies were identified. Trials are ongoing, but are no longer recruiting new patients. (4) In addition, this device still does not have clearance or approval from the FDA. Thus, the policy statement is unchanged.

2009 Update

The policy was updated with a literature search through November 2008. Reports of 2 small studies with early, intermediate outcomes were identified. Vargas and colleagues reported on a study of 15 patients who received preoperative focused-microwave thermotherapy in combination with neoadjuvant
anthracycline-based chemotherapy for invasive (T2, T3) breast cancer. (5) Compared with 13 patients who received only the anthracycline-based regimen, there was greater (88% vs. 59%) tumor volume reduction in the experimental group. Dooley and colleagues reported on a randomized study of preoperative focused-microwave thermotherapy for early-stage breast cancer. (6) In this study, 34 patients received thermotherapy before surgery and 41 received only surgery. Positive margins were found in 10% (4 of 41 controls) compared with 0% (0 of 34) in the experimental group (p =0.13). These studies provide insufficient data to change the policy statement. Studies involving larger numbers of patients with longer follow-up of clinical outcomes are needed.